Question

Помогите решить 3 последних номера (11;12;13) даю 50 баллов!!!!

Answer 1

11. ((2m-5n)(2m+5n)/(2+m))*(m²-2m+4)/((2m+5n)/(m²-2m+4))=(2m-5n)/(2+m)

12. (3xy+y²-3xy)/(x*(3x+y)=y²/(x*(3x+y))

13. x/(y*(x-y))-y/(x*(x-y))=(x²-y²)/(xy*(x-y))=(x+y)(x-y)/(x*y*(x-y))=(x+y)/(xy)